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Serializing object that contains cyclic object value
... goes.
One feature that's not as well-known as JSON.stringify() is console.table(). Simply call console.table(whatever);, and it will log the variable in the console in tabular format, making it rather quite easy and convenient to peruse the variable's contents.
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Split value from one field to two
I've got a table field membername which contains both the last name and the first name of users. Is it possible to split those into 2 fields memberfirst , memberlast ?
...
Rails migrations: self.up and self.down versus change
... you rollback? Of course it's remove_column. What is the inverse of create_table? It's drop_table. So in these cases rails know how to rollback and define a down method is superfluous (you can see in the documentation the methods currently supported from the change method).
But pay attention becaus...
Interface or an Abstract Class: which one to use?
...along a particular path. Other times it would be bad. Imagine if PHP's Countable and Iterator interfaces were abstract classes instead of interfaces.
One approach that's common when you're uncertain which way to go (as mentioned by cletus below) is to create an interface, and then have your abstr...
How to save MySQL query output to excel or .txt file? [duplicate]
...g to write the file to.
Syntax
SELECT Your_Column_Name
FROM Your_Table_Name
INTO OUTFILE 'Filename.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\n'
Or you could try to grab the output via the client:
You could try executing the query from the you...
Is floating point math broken?
...754 is anything with an error of less than one unit in the last place. The table of reciprocals of Y (1/Y) is known as the quotient selection table (QST) in the slow division, and the size in bits of the quotient selection table is usually the width of the radix, or a number of bits of the quotient ...
What does multicore assembly language look like?
.... All that's needed is software support for each thread to set up its own tables and messaging queues. The OS uses those to do the actual multi-threaded scheduling.
As far as the actual assembly is concerned, as Nicholas wrote, there's no difference between the assemblies for a single threaded or...
Naming convention for unique constraint
...rimary key and foreign key have commonly used and obvious conventions ( PK_Table and FK_Table_ReferencedTable , respectively). The IX_Table_Column naming for indexes is also fairly standard.
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What does SQL clause “GROUP BY 1” mean?
...d name, you may also group by ordinal, or position of the field within the table. 1 corresponds to the first field (regardless of name), 2 is the second, and so on.
This is generally ill-advised if you're grouping on something specific, since the table/view structure may change. Additionally, it ma...
How can I select multiple columns from a subquery (in SQL Server) that should have one record (selec
...
select t1.*, sq.*
from table1 t1,
(select a,b,c from table2 ...) sq
where ...
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